I like Definitive Technology too. I forgot about them for some reason. I have not heard their bookshelf speakers, but I imagine they are pretty good. They do have the non-powered towers which could save you quite a bit of money. Many, if not all (towers anyway, haven't looked at anything but big surround systems from them), Def Techs are 4-8 ohms, so you would be getting 300 Watts from the amp into a speaker around 91 db sensitivity.

I have been happy with the sound. (Rooms about 13 x 12 ? with a large arched opening at one end/door sized arch at other).
I bought Definitive Tech’s. (first thing I researched, back when I didn’t even understand what Frequency response related to)

ProCenter C2: Freq RL 45 Hz-30 kHz 4-8 ohm outputs Rec. Assoc Amplication: 10-200 watts
Drivers: Two 5 1/4" cast basket high resolution, high power, bass-midrange drivers with mineral filled polypropylene cones, butyl rubber surrounds and dust caps, and one 1" ferrofluid-dampened pure aluminum dome tweeter. EFF: 91 dB
ProSub 200TL: Freq: 18 Hz-150 Hz Builtin: 250 watts RMS
Driver: One high-definition 12" driver with polymer cone.
HP Xover: 6 dB/octave speaker level at 80 Hz
LP Xover: 24 dB/octave continuously adjustable variable (40-150 Hz)
Inputs: Low-Level: Gold plated RCA left, right and direct LFE in Speaker Level Inputs: 5 way gold plated binding posts left and right channel.
Outputs: Speaker Level Outputs: 5 way gold plated binding posts left and right channel.
My Front’s and surrounds:
ProMonitor 100: Freq: 50 Hz-30 kHz 4-8 ohm outputs Rec. Assoc Amplication: 10-175 watts
Drivers: 5 1/4" cast basket bass-midrange driver, 1" pure aluminum dome tweeter, blended with complex, phase coherent Linkwitz-Riley crossover.
Eff:: 90 dB

As a general rule of thumb, bigger speakers can handle power better. I think that’s part of my problem, I want to know what larger towers would sound like. I should look at the towers in Def Tech.
as their line is considered interchangeable as to voicing, (I believe).

Right now, I have to tear away from my comfort zone,,,and sniff sniff/cough cough, catch up on some major work thats piling up. I cut and pasted specs should have condensed them but have to run.

Lena,

To be honest, your amp is probably way too much for those little speakers. Depending on where you have them crossed over, they really probably can't handle much more than 100W, if even that. However, in a room that sized, and given the speaker's efficiency, I would actually be kind of surprised if they are giving you problems. Your ears should probably be bleeding before the speakers give up on you. However, if you really are cranking the system, some more robust speakers are probably in order.

Def Tech's non-powered towers are really quite good. Most of them are bi-polar, meaning they fire sound from the front and the back. It gives a more "diffuse" sound. For two channel music, it's kind of pleasant, although the imaging may not be quite as good. In any event, one of their dual-woofer 5-1/4" towers would probably get you stepped up for output and power handling.

I've never seen the crossover in a Def Tech speaker, but from their literature, it sounds like they actually give it some thought. Based on the independent frequency response measurements I've seen of their speakers, they are probably pretty well designed. So, despite making a "hasty" decision on your speakers, you picked a good brand. The unfortunate thing is that they probably weren't intended for such a monsterous amp! Down the road, if you decide to upgrade, atleast you should only have to do the mains, and maybe the center, if you don't feel it's up to par. The surrounds should be pretty close to being "voice matched", so I wouldn't think they would need to be upgraded. They don't normally see the same kind of power (at least not for very long durations) as the front speakers, so they will probably serve you fine.

Jason

Jason,
Thank you I guess in my backdoor method that was partially what I was digging for. Opinions on the specific specs on my speakers with the 770.

I think its good odds, the vibration incident was set off by a combo of the son moving things in the attic, and a song that hit the right frequency to start it off. I checked the screw which adjusts tilt/turn on the bracket, it is loose, (need to find the little tighten provided) and rotating the speaker ‘tames’ the vibration.
So hopefully, I have not blown anything yet!
The 950 can be absolutely sublime with the right mix of source and setup, I believe I’d like to know what it could do with a broader frequency range. I do need to factor in any future buy, my tendency to crank it up when its sounds good and the FOL that the younger guys will consistently push any system.
I think its time to start paying attention to speaker threads

I did head out the door to look at those ‘nifty’ Bose size speakers, but came home with the Def Techs, so I put what limited capability of ‘thought’ I had into it. I ended up taking it on ‘paper’ faith, while researching could not access the models in stock within a shopping range I could get to during my crunched timeframe. Just located a dealer and ordered without a demo.

I have them crossed over at 80 right now. I’ve played with 120 and 100, and the effects are generally not as across all sources pleasing as leaving them at 80. I need to study up on the sub integration, (I’ve never even read my sub manual so I need to brush up there). When using 120, I think I had something on the sub out of whack, which resulted in some gaps between the crossovers.

One ‘effect’ that impressed me on 'Donnie Darko' was the utterly seamless soundstage on the thunder track rolling from L to R and Fronts to backs. Now that was nifty and a rather nice “Outlaw Moment”.

Ugh back to work.
Thanks again Jason.

I think Definitive Technologies is a very good brand too. If you're still not happy with the power output, check with the store you bought them at about an upgrade policy. The places I have looked at have a one year trade up where you can return the speakers you bought and put the money you paid for them into a more expensive set. This was huge for me when I decided I could do better than Bose 701. I traded those in for $900 (I bought them on sale) for Mirage OM-5 floor models marked down to $2000. So I paid $1100 for $3500 speakers! The two places I've shopped are Tweeter and Sound Forum.

I know with Definitive Tech towers and surrounds, all you have to do is match the midrange driver, ie all speakers should have 4", 5.25", or a 6.5" midrange. This applies to power towers, unpowered, surrounds and the center channels. So in your case, you should be fine with anything that has the 5.25" midrange.

I think I would agree with JasonA that the amp is a bit strong for these speakers. DefTechs go 4-8 ohms impedance and, to my understanding, the amp will run at 4 ohms giving 300 Watts to each speaker. If I'm wrong the amp stays at 8 ohms, I think it would be a fantastic match.

A very easy speaker-protection system you should consider is in-line fuses. I've always used them to protect my drivers after frying an expensive 15" woofer 30 years ago. My Crown amps in fact have line-output fusing built in.

In terms of amps, I believe that a high damping factor also reduces the likelihood of driver damage at any given SPL.

In terms of overall speaker build, my first criterion is the weight of the cabinet. Its really pretty accurate to say that, for numerous reasons, the heavier the cabinet, the better. Of course, this is problematic if you want to hang speakers from walls or ceilings! (I choose not to).

In terms of really bullet-proof speakers, I would have to say the JBL pro line of drivers. A home user would have to work mighty hard to put out a signal that could blow them, and they sound wonderful for heavy rock, but IMHO are insufficiently "fast" or accurate for more subtle music types.

In terms of home-building or kits, I think Jason is over-selling a bit. On the one hand, you will almost certainly have drivers that are technically of higher quality than any finished speakers retailing for under a grand apiece (that's right, apiece not pair), maybe even $1500. On the other hand, true high-end stuff such as Linn (my own favorite), Thiel, etc., is providing a designed / tuned package of crossover / cabinet design and construction that the kits and the home designers rarely equal.

Its curious to me about Def Tech - consistently seems that people either really like their sound or really dislike their sound. Also seems that in general, those whose main interest is HT prefer them compared with people whose main interest is music. I would never call them a "bad" brand or sound, but to my ears they lack clarity in the high end and their bass is overly prominent and somewhat muddy. Having said that, I would take them over anything in the Bose line.

The Def Tech's are extremely heavy for such little things, All the guys who picked up a speaker were surprised at the weight to size ratio.
Soooo...I'm at least one step above Bose..
For what they are I'm happy with them and would recomend them when looking for that 'sized' speaker.

The bass has not really been a prob. (running a sub with them) with the crossovers set right they do handle the HT well. You are correct I started to buy a SW for the husband to suppliment his HT experince, and ended up with the set. So the leaning was heavy towards HT on this purchase. I've found the highs to have decent clarity in these, (this coming from a newbie just starting to pay attention) however they seemed harsh i the highs the first weeks. The harshness seems to have settled down, and on most recordings do not seem to display that tendency as much, I don't know how much of the early tweaking I did affected this or if there is something to 'burn in'.
If and when I upgrade, I'm the sort that looks at many angles, and one angle for me (on a major speaker purchase) would be the quality of the build as relates to longivty and would they have to be carefully monitered to prevent damage, or can I just relax and play the music.

Norman,
To a certain extent I agree with you. Without doubt, its simple to spend a fortune on really great drivers and crossovers, and have it sound horrible. Designing your own speakers takes a lot of work, knowledge, and in most cases some good measurement equipment. HOWEVER, there are a ton of proven designs available. There are lots of "kits" available that would give you 90% of the Linn/Thiele/etc. experience for half the cost. Suppose you want that last 5-10%...there are designs out there for those as well. Stuff from Northcreek is supposed to be exceptional, and I would guess compares very, VERY closely with the top dogs out there.

Here's another thing to consider (and I may be tying the rope to hang myself), I don't think that speakers are quite as critical for HT use as they are for music. That's probably an over-generalization, but here are some of my thoughts. First, in music listening, and particularly in straight stereo, phasing is EXCRUCIATINGLY important for a good image and soundstaging. You need good speakers to bring out all of the details, instrument harmonics, and subtlties of a good recording. Also, in the music scene, the speakers actually have to paint the picture. Good speakers will properly locate instruments in a symphony, or the guitarist on stage at a concert. The audio gear is all there is for music listening.

On the HT side, speakers are just one part of the system. When watching a movie, you have an initial distraction of a video source in front of you. Your brain now has to process sights and sounds, and probably can't do both CRITICALLY at the same time. You also have to keep up with the plot, characters, etc., so now you've got both sides of the brain going. My point is that you are probably less able to critically listen to the sound, as there is lots of other stuff going on to distract you.

The design of speakers for HT use is also quite different than for music. Music listening will often involve a room where there are a couple of good seats to listen from. The speakers are optimized for this type of environment. For HT, the speakers are often designed to cover a larger area, so that there is reasonable coverage throughout the room.

I agree that the Def Tech stuff is not to be categorized as "high end", but for the money, I think they are better than a lot of the stuff out there. One thing I've noticed about them, though, is that everytime I hear their powered speakers in a store, they have the sub level set WAY too high. I supposed that's a marketing gimmic, but to someone who knows what good sound is, it sounds horrible. Properly adjusted, they actually sound decent. Compared to many of the other manufacturers in the same price range, I think the Def Tech stuff holds up very well. I think their construction techniques are much better than most, as well. They don't spend any money on veneers or fancy cosmetics, so the money can go into building a rugged cabinet.

Okay, enough of my preaching.

Jason

You are right about that Jason- it's that last 10% that will cost you the big bucks.

Nicely worded warning noted, - and taken to heart, that’s why there would have to be a lot of planning and resources gathered to get into this. But it might be fun trying. In his first life when young my husband worked at a cabinet shop which did custom penthouses etc. that’s the only step in the process we would have handled.

The cabinets really a minor, just icing on the cake, and I know that. Its like a beautiful woman with no brain, you can only ‘look’ for so long, and then she speaks…..

I’ve seen it argued often that a good speaker which can handle 2-channel beautifully will always be more adept at producing an HT experience but I completely agree with you Jason. All the psychological distractions of HT make it much easier to enjoy an HT experience with speakers not so blessed with that ‘hi-fi’ sound.